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A Project of The Annenberg Public Policy Center
SciCheck’s COVID-19/Vaccination Project

How do we know vaccines are safe?

No vaccine or medical product is 100% safe, but the safety of vaccines is ensured via rigorous testing in clinical trials prior to authorization or approval, followed by continued safety monitoring once the vaccine is rolled out to the public to detect potential rare side effects. In addition, the Food and Drug Administration inspects vaccine production facilities and reviews manufacturing protocols to make sure vaccine doses are of high-quality and free of contaminants.

How safe are the vaccines?

Hundreds of millions of doses of COVID-19 vaccines have now been administered in the U.S. and only a few, very rare, safety concerns have emerged. The vast majority of people experience only minor, temporary side effects such as pain at the injection site, fatigue, headache, or muscle pain — or no side effects at all. As the CDC has said, these vaccines “have undergone and will continue to undergo the most intensive safety monitoring in U.S.

No Evidence Vaccines Impact Fertility

No Evidence Vaccines Impact Fertility

Q: Do the COVID-19 vaccines cause infertility?
A: There’s no evidence that approved vaccines cause fertility loss. Although clinical trials did not study the issue, loss of fertility has not been reported among thousands of trial participants nor confirmed as an adverse event among millions who have been vaccinated. 

How were safe and effective vaccines developed so rapidly?

The unprecedented speed of the COVID-19 vaccines was due to multiple factors.
Candidates for an mRNA vaccine — the technology used for the Pfizer/BioNTech and Moderna vaccines — can be quickly designed once scientists know the genetic sequence of the virus and which protein to target. Researchers already knew from past experience with SARS and MERS, which are other diseases caused by coronaviruses, that the spike protein the virus uses to enter cells was likely the right one.

Video Makes Bogus Claims About ‘War Crimes’ and COVID-19 Vaccine Safety

Video Makes Bogus Claims About ‘War Crimes’ and COVID-19 Vaccine Safety

A video falsely claims that people receiving authorized COVID-19 vaccines are taking part in a deadly clinical trial and that those administering the doses are war criminals under the Nuremberg Code. That’s bogus. People getting the vaccines, which have been shown to be safe and effective, consent to receive them and aren’t participating in research.

Video Uses Bogus Claims to Stoke Race-Based Fears of COVID-19 Vaccine

Video Uses Bogus Claims to Stoke Race-Based Fears of COVID-19 Vaccine

A viral video clip makes bogus claims about COVID-19 vaccines and falsely accuses the government of “pure racism” for “push[ing] this heavily on Blacks and browns.” Public health experts have recommended prioritizing those communities for the vaccine because they have suffered higher rates of infection and death.

Hank Aaron’s Death Attributed to Natural Causes

Hank Aaron’s Death Attributed to Natural Causes

Baseball legend Henry “Hank” Aaron died from natural causes, according to the medical examiner’s office in Fulton County, Georgia. There’s no evidence that his death was a result of being vaccinated against COVID-19 in early January, as multiple posts on social media suggested.

A Guide to Moderna’s COVID-19 Vaccine

A Guide to Moderna’s COVID-19 Vaccine

Moderna’s mRNA vaccine is the second COVID-19 vaccine authorized for use in the U.S. Here, we give a rundown of basic facts about the vaccine and an overview of how it works.